JP2997089B2 - Optical pickup device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup device used for an optical information recording / reproducing apparatus for recording / reproducing optical information on / from an optical information recording medium such as an optical disk. More specifically, the present invention relates to an optical pickup device configured to enable random and high-speed access using the optical pickup device.

[0002]

2. Description of the Related Art An apparatus for recording / reproducing information on a single optical disk by using a plurality of optical pickups is disclosed, for example, in Japanese Patent Application Laid-Open No. 62-40646. is there. FIG.
FIG. 1 is a diagram showing a configuration of an optical information recording / reproducing device disclosed in Japanese Patent Publication No. 46-46. In this apparatus, a plurality of optical pickups 101a to 101d, each of which can be accessed independently, are arranged radially with respect to the rotation center 102 of an optical disk, and the optical pickups are randomly and desirably positioned at desired positions. It enables high-speed access to record / reproduce information.

An information recording medium such as an optical disk is usually housed in a cartridge for protecting the surface of the medium or for facilitating handling. FIG.
FIG. 3 is a plan view showing the structure of a cartridge generally used at present. As shown in FIG. 11, an opening 105 is provided on one surface of the cartridge 104,
A light beam is applied to the information recording surface of the information recording medium through the opening 105 to record / reproduce information.

[0004]

However, FIG.
In the information recording / reproducing apparatus shown in FIG. 1, optical pickups are arranged radially, and the general cartridge shown in FIG. 11 has only one opening on one side when viewed in the diameter direction of the recording medium. Not applicable to information recording media stored in cartridges. Further, since as many as four optical pickups are arranged in a radial pattern, the volume occupied by the optical pickups in the device increases, and there is a disadvantage that the size of the entire device cannot be reduced.

When a plurality of optical pickups access an information recording medium housed in a general cartridge as shown in FIG. 11, the plurality of optical pickups are arranged side by side in the track direction. It is necessary to reduce the size of the optical pickup in the track direction to reduce the distance between the objective lenses. However, since each optical pickup requires a magnetic circuit for driving the objective lens and a guide rail for guiding the optical pickup in the tracking direction, it is difficult to reduce the dimensions of the optical pickup in the track direction. Was.

An apparatus in which the size of an optical pickup in the track direction is reduced is disclosed, for example, in Japanese Patent Application Laid-Open No.
There is one described in Japanese Patent No. 924. FIG.
FIG. 2 is a perspective view illustrating a configuration of the optical pickup device. In this apparatus, the carriage 1 on which the objective lens 110 is mounted
Since the guide rails 113a and 113b for guiding the track 11 in a direction perpendicular to the track and the magnetic circuit for driving the carriage 111 on which the objective lens is mounted are laid out up and down in the focus direction, the dimension in the track direction is reduced. ing. However, carriage 1
11 support center, that is, two guide rails 113a
And the drive point for driving the carriage in the direction perpendicular to the track are vertically displaced when viewed in the tracking direction, so that the moment when the carriage moves in the direction perpendicular to the track is This causes a problem that resonance is likely to occur.

The device described in Japanese Patent Application Laid-Open No. 63-50924 is an optical pickup equipped with one objective lens, and an information recording device having a plurality of pickups by arranging two such optical pickups in parallel. When a reproducing apparatus is configured, two sets of magnetic circuits required to drive one objective lens are arranged in the track direction, so that the distance between each objective lens cannot be shortened. . Therefore, even if the information recording / reproducing apparatus is used to record / reproduce information on / from an information recording medium housed in a general cartridge as shown in FIG. It will not fit.

Further, since the distance between the two objective lenses is large, the moving direction of the optical pickup differs depending on whether the two optical pickups are moved to the inner circumference side or the outer circumference side of the disk. Since the angle formed between the spot hit by the track and the tangential direction of the track greatly changes, there is a problem that the track error signal is likely to change.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems and provides an information recording medium provided with a plurality of optical pickups, which can be accessed at random and at high speed, and which is housed in a generally used cartridge. It is an object of the present invention to provide an applicable optical pickup device.

[0010]

In order to solve the above problems, a first invention of the present application is to provide two optical elements for irradiating a light spot on an information recording surface of an optical information recording medium, Two carriages on which optical elements are respectively mounted, and moving these carriages in a first direction across an information recording track formed on the information recording medium on one side of the optical information recording medium in a diametrical direction. Supporting means for supporting the plurality of optical elements in a second direction substantially perpendicular to the information recording surface; and supporting means for independently driving the two carriages in the first direction. An optical pickup device comprising: a driving unit for moving; a center of gravity of an optical pickup including the carriage and a member supported by the carriage; and a driving center of the driving unit. At least a portion of the supporting means with which match, when supporting the plurality of carriages, is characterized in that it is used in common.

As described above, in the optical pickup device according to the first aspect of the present invention, at least a part of the two supporting means for mounting the optical elements and supporting the independently operating carriages respectively includes the plurality of carriages. Are commonly used to support the distance between the optical elements. Therefore, information can be recorded / recorded on an information recording medium stored in a generally used cartridge.
Can be applied to playback. Further, since the distance between the optical elements can be reduced, the moving direction of the optical pickup, which occurs when the optical element is moved to the inner peripheral side of the disk and when the optical element is moved to the outer peripheral side, hits the spot. The difference in angle between the point and the tangential direction of the track becomes smaller. Therefore, information can be recorded / reproduced accurately without changing the track error signal.

According to a second aspect of the present invention, there are provided a plurality of optical elements for irradiating a light spot on an information recording surface of an optical information recording medium, a plurality of carriages for mounting these optical elements, respectively, Support means for movably supporting a carriage in a first direction transverse to a direction of an information recording track formed on the information recording medium on one side of the optical information recording medium in a diameter direction; A light comprising: optical element driving means for independently driving elements in a second direction substantially perpendicular to the information recording surface; and carriage driving means for independently moving the plurality of carriages in the first direction. In the pickup device, at least a part of the optical element driving unit is commonly used for driving the plurality of optical elements in the second direction, and / or , At least a portion of said carriage drive means, upon driving the carriage in the first direction, it is characterized in that it is used in common.

As described above, in the second aspect of the present invention, at least a part of the optical element driving means is commonly used for driving a plurality of optical elements in the second direction.
And / or at least a part of the carriage driving means,
When the carriage is driven in the first direction, it is configured to be commonly used, so that the distance between the optical elements can be shortened as in the above-described first invention, and a commonly used cartridge can be used. The information on the stored information recording medium can be used for recording / reproduction. Also, the angle formed between the moving direction of the optical pickup and the tangential direction of the track at the point where the spot hits occurs when the plurality of optical elements are moved to the inner circumference side of the disk and when the plurality of optical elements are moved to the outer circumference side. Since the difference is small, the track error signal does not change, so that information can be recorded / reproduced accurately.

According to a third aspect of the present invention, a plurality of optical elements for irradiating a light spot on an information recording surface of an optical information recording medium, a plurality of carriages for mounting these optical elements, and these carriages are provided. On one side of the optical information recording medium as viewed in the diameter direction, supporting means for movably supporting the optical information recording medium in a first direction across an information recording track formed on the information recording medium; and An optical pickup device comprising: an optical element driving means for independently driving in a second direction substantially perpendicular to an information recording surface; and a carriage driving means for independently moving the plurality of carriages in the first direction. The optical element driving means includes an optical element driving coil and an optical element driving magnetic circuit, and at least a part of the optical element driving magnetic circuit includes the plurality of optical elements. Upon driving the child in the second direction, it is characterized in that it is used in common.

As described above, in the third invention of the present application, the optical element driving means includes the optical element driving coil and the optical element driving magnetic circuit, and at least a part of the optical element driving magnetic circuit includes a plurality of optical element driving magnetic circuits. When the optical elements are driven in the second direction, they are commonly used, so that the distance between the optical elements can be shortened, and the same effects as those of the first and second aspects can be obtained. is there.

According to a fourth aspect of the present invention, there are provided two optical elements for irradiating a light spot on an information recording surface of an optical information recording medium, and these optical elements are respectively mounted thereon, and the diameter of the optical information recording medium is adjusted. The first side crossing the direction of the information recording track formed on the information recording medium on one side as viewed in the direction.
Two movable parts configured to be movable in the directions of
Optical element driving means for independently driving two optical elements in a second direction substantially perpendicular to the information recording surface; and movable section driving means for independently moving the two movable sections in the first direction. In the optical pickup device, the center of gravity and the drive center of the optical pickup including the movable portion and the member supported by the movable portion coincide with each other, and the two optical elements, when viewed in the first direction, are different from each other. The movable units are arranged so as to be shifted from the respective centers in a direction approaching each other, and at least a part of the support unit and the driving unit are commonly used in driving the two movable units in the first direction. It is characterized by having.

As described above, according to the fourth aspect of the present invention, the two optical elements are arranged so as to be shifted from the respective centers of the movable portions in the direction approaching each other when viewed in the first direction. Can be shortened, and at least a part of the supporting means and the driving means are commonly used for driving the two movable portions in the first direction. The same effects as those of the second and third inventions can be obtained.

[0018]

FIG. 1 shows a first embodiment of an optical pickup device according to the present invention.
2 is a partially exploded perspective view, and FIG. 3 is a side view seen from a direction perpendicular to a track on an information recording medium. In the following description of the embodiments, a direction perpendicular to a track formed on an information recording medium is defined as an X direction, a tangential direction of a track is defined as a Y direction, and a direction perpendicular to the information recording medium is defined as a Z direction.

As shown in FIG. 1, two optical pickups 3
9a and 39b are arranged side by side in the Y direction, and these optical pickups 39a and 39b are configured to be movable in the X direction of the optical disc 1. Reference numeral 3 denotes a spindle motor for rotating the optical disc 1. A fixed optical system 41 is provided beside each of the optical pickups 39a and 39b.
a, 41b are arranged, and the light beams emitted from these fixed optical systems are introduced into the optical pickups 39a, 39b, and the objective lenses 10, 1 included in the optical pickups are provided.
The recording / reproducing of information is performed by irradiating the track 2 via the “0”. The optical pickups 39a and 39b are formed identically, and the following description will be made only for one optical pickup.

As is apparent from FIG. 2, the objective lens 10
The lens holder 11 is placed on the lens holder 11.
Focus coils 12, 12 wound in a square shape are respectively fixed to both side surfaces in the X direction. Convex portions 11a are provided on both side surfaces of the lens holder 11 in the Y direction.
Are formed, and two springs 13 are attached to the upper and lower side surfaces of these convex portions 11a to support the lens holder 11 movably in the Z direction. A total of four springs 13 extend to the side of the lens holder 11 in parallel with each other, and the other end of the spring 13 is fixed to a holding member 14. The spring 13 is made of beryllium copper and has a thickness of 0.1 mm.
Around a thin plate, coated with butyl rubber is used to take damping.

The carriage 18 includes the lens holder holding section 1
8a and a carriage coil holding portion 18b. As is apparent from FIG. 3, these holding portions are arranged so as to be oblique as viewed from the X direction. Lens holder holder 18a
On the upper side surface, convex portions 18c and 18d are formed,
The lens holder 11 is arranged between these convex parts. The holding member 14 described above is fixed to the outer surface of the one convex portion 18c. Magnets 15, 15 and yokes 16, 16 are arranged in gaps formed between the side surfaces in the X direction of the lens holder 11 and the projections 18c, 18d, respectively. The outer surfaces of the yokes 16, 16 made of an iron plate are fixed to the inner surfaces of the protrusions 18c, 18d, respectively.
The outer surfaces of the magnets 15 are fixed to the inner surface of the yoke 16, respectively. The inner surfaces of the magnets 15 and 15 are magnetized in two directions in the Z direction so that different poles face each other, and the magnetized surfaces of the two poles are formed by winding the first pole in a square shape. The second pole is located on the upper side of the focus coil 12 so as to face the lower side.

The lens holder holding portion 18 of the carriage 18
An opening 18e is provided at the center of a, and a mirror 17 is fixed in the opening 18e. A through hole 18 penetrating from one side surface to the opening 18e is provided.
f is formed to extend in the X direction, and the fixed optical system 41
The light beam from a is guided to the mirror 17 through the through hole 18f, where it is reflected and guided to the objective lens 10. Further, the lens holder holding portion 1 of the carriage 18
A bearing fixing part 18g is provided on the side of the X direction of 8a.

As shown in FIG. 3, a reference guide rail 30 is provided between the carriages 18 of the two optical pickups 39a and 39b so as to extend in the X direction. The subordinate guide rail 31, so as to face diagonally with the reference guide rail 30,
31 are provided. Two bearings 19a, 19a are press-fitted and fixed to respective bearing fixing portions 18g provided on the lens holder holding portion 18a of the carriage 18. On the other hand, one bearing 19b is provided on the bottom of the carriage coil holding portion 18b of the carriage 18.
On the upper side, a bearing 19c for preload is fixed by a screw 21 via a stainless steel spring 20. The four bearings 19a are brought into contact with the reference guide rail 30, and the bearings 19b and 19c are connected to the subordinate guide rail 31.
To the carriage 1 by the guide rails 30, 31 and the bearings 19a, 19b, 19c.
8 is movably supported in the X direction.

The carriage coil holding portion 18b of the carriage 18 is provided with two carriage coils 22a and 22b. That is, the carriage coil 22
The carriage coil 22b is connected to the carriage coil holding portion 18a so that the inner surface a of the carriage coil holding portion 18b contacts the bottom surface of the lens holder holding portion 18a.
b and the outer surface in the Y direction of the lens holder holding portion 18a.
It is arranged in a direction crossing the arrangement of the reference guide rail 30 and the subordinate guide rail 31. The yokes 34a and 37 are arranged in the carriage coils 22a and 22b, respectively. The magnet 35 is arranged at a position facing the carriage coil 22b arranged on the upper side, and a magnetic gap 29a cooperating with one side of the carriage coil 22b is formed between the carriage coil 22b and the magnet 35. The magnet 35 is fixed inside the long side of the U-shaped yoke 36, and is (magnet 35)-(yoke 37)-(yoke 36)-
A magnetic circuit composed of the (magnet 35) is formed.

Similarly, a yoke 34a is disposed inside the carriage coil 22a disposed on the lower side, and the magnet 32 is disposed at a position facing the carriage coil 22a.
To form a magnetic gap 29b cooperating with the carriage coil 22a. The yoke 34b is arranged symmetrically with the magnet 32 interposed therebetween. The magnet 32 is fixed to a yoke 33 bonded to the ends of the yokes 34a and 34b, and is composed of (magnet 32)-(yoke 34b)-(yoke 33)-(yoke 34a)-(magnet 32). A magnetic circuit is formed. The thicknesses of the magnet 32 and the magnet 35 are determined so that the magnetic flux density of the magnetic gap 29a and the magnetic flux density of the magnetic gap 29b are the same.

As is apparent from the above description, each of the optical pickups 39a and 39b is
And various members supported by the carriage, which together constitute a movable part that moves in the X direction.

In this embodiment, two optical pickups 3
9a and 39b have the same configuration and are provided facing each other, and a magnet 32 which forms a magnetic circuit for driving the reference guide rail 30 and the inner carriage coil 22a is commonly used. As is evident in FIG.
When viewed from the X direction, the first carriage coil 22a
And the driving point F of the second carriage coil 22b.
, And the intersection of the line SS connecting the center S of the reference guide rail 30 and the center S of the driven guide rail 31 passes through the center of gravity G of the optical pickup 39a. Therefore, when the optical pickup 39a moves in the X direction, no rotational moment is generated, and resonance hardly occurs.

The optical pickups 39a and 39b are mounted on a base (not shown). The spindle motor 3 for rotating the disk 1, the fixed optical systems 41a and 41b, and the guide rails 30 and 31 are mounted on the base. , Yoke 3
3, 34a, 34b, 36 and 37 are fixed.
The two fixed optical systems 41a and 41b have exactly the same configuration but are fixed in opposite directions.

Next, the operation of the present embodiment will be described with reference to FIGS. As is clear from FIG.
Reference numerals a and 41b each include a laser 42, a photodetector 43, and a beam splitter 44. A light beam emitted from the laser 42 is reflected by a galvanometer mirror 40, and is set in an opening 18e of the carriage 18 of the optical pickups 39a and 39b. The light is reflected by the mirror 17, guided to the objective lens 10, collected, and forms a spot on the disk 1. The light beam reflected by the disk 1 again passes through the objective lens 10, is reflected by the mirror 17 and the galvanometer mirror 40, is bent in an optical path by a beam splitter 44 installed in the fixed optical system 41, and is transmitted to the photodetector 43. Incident.

As is apparent from FIG. 3, in this embodiment, the movable parts of the optical pickups 39a and 39b including the objective lens 10, the reference guide rail 30 and the bearing 19a are provided in the opening provided in the cartridge 4 of the optical disk 1. 5 is located within.

When an electric current is applied to the focus coil 12, the magnetic field generated by the two magnetic poles magnetized on the magnet 15 and the focus coil 12 cooperate to make the focus direction (Z
Direction), the spring 13 is deformed, and the objective lens holder 11 moves in the focus direction.
On the other hand, when a current is applied to the carriage coil 22a or 22b, a force in the X direction is generated in cooperation with the magnetic field generated by the magnet 32 or 35, and the entire optical pickup is moved in the X direction along the guide rails 30 and 31. Will move. As described above, the two objective lenses 10 and 10 are contained in the opening 5 of the cartridge 4 to facilitate random and high-speed access. Further, since the guide rail 30 and the magnet 32 are shared by the two pickups, the distance between the objective lenses 10 and 10 is reduced, and the distance between the objective lens 10 and the information recording medium housed in a conventionally used cartridge is generally reduced. It can be applied to recording / reproduction.

FIG. 4 is a plan view showing a modification of the optical pickup device according to the first embodiment. In the first embodiment, one of the fixed optical systems 41a and 41b for making a light beam incident on the optical pickup is configured such that one of the fixed optical systems 41a and 41b
The other is arranged to guide the objective lens 10 from the outside of the disk 1. In this modification, both fixed optical systems guide the light beam from the spindle motor 3 side to the optical pickup. It is composed. Therefore, in this modification, the fixed optical systems 41a and 41b can be positioned closer to the center of the disk 1, and a smaller optical information reading device can be provided.
In this case, if the through holes 18f provided in the objective lens holding portion 18a of the carriage 18 shown in FIG. 2 are provided on both sides of the opening 18e, manufacturing becomes easy. The mirrors 17 are arranged so that the directions of the mirrors 17 with respect to the optical pickup in the opening 18e are opposite to each other. Also,
The holding member 14 is provided with the protrusions 18 c and 18 d of the carriage 18.
And fix them in reverse.

FIG. 5 is a partially exploded perspective view of a second embodiment of the present invention, and FIG. 6 is a side view. The same parts as those in the above-described first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the second embodiment, a focus coil 51 bent and wound in a U-shape is fixed to the bottom surface of a lens holder 50. A hole 50a for guiding a light beam from the fixed optical system 41 (see FIG. 1) is provided on a side surface in the X direction of the lens holder 50, and a carriage 5 is provided on a side surface in the Y direction.
2, a hole 50b through which an arm 52a passes is formed, and the mirror 17 is fixed to the tip of the arm 52a. A fixing member 14 that supports one end of each of the four springs 13 is fixed to the center side surface of the arm 52a. Carriage coils 53, 53 are wound around the end of the carriage 52 in the X direction. The carriage 52 is provided with two convex portions 52b, 52b in the X direction.
Holes for press-fitting and fixing the bearing 53a are formed in the respective convex portions 52b, 52b. Also, the carriage 5
A spring 20 is fixed to the center of the upper surface of the spring 2 via screws 21, and a preload bearing 53 b is fixed to the tip of the spring 20. In the carriage coil 53, a yoke 59 having magnets 58a and 58b attached to both sides.
Is inserted. The long side of the L-shaped yoke 60 faces the outer magnet 58a, and the side surface of the center yoke 55 faces the inner magnet 58b.

The yoke 61 includes a yoke 59 and a center yoke 5.
5 is connected. A V-shaped groove 55a is formed on the side of the yoke 55 facing the magnet 58a in the X direction, and functions as a guide for moving the optical pickup in the X direction. A U-shaped groove 58c is formed on the surface of the magnet 58a facing the yoke 55, and the bearings 53a, 53a contact with the V-shaped groove.
Does not hit the magnet 58a.

On the upper surface of the yoke 55, two sets of convex portions 55b,
55c extend along the X direction, and the outer convex portion 5
Magnets 57, 57 are fixed to the inner side surfaces of 5b, 55b, and a magnet 56 is fixed to the middle between the inner protrusions 55c, 55c. Magnets 56 and 57
Are magnetized such that the same poles face each other. When the optical pickup 54 is assembled, the bent portions 51a, 51a of the focus coil 51 are configured to be located over the convex portion 55c inside the yoke 55, and the bent portion 51a is formed inside the yoke 55. The protrusion 55c and the magnet 56, and the protrusion 55c and the magnet 57
And will be located in the magnetic gap formed.

The magnetic circuit for the focus coil 51 is
(Magnet 56)-(Protrusion 55 inside yoke 55)
c)-(Yoke 55 body)-(Inner convex portion 55c)-
(Magnet 56) and (magnet 57)-(projection 55c)-(yoke 55)-(projection 55b)-(magnet 57).
It is commonly used to drive two objective lenses in the focus direction. On the other hand, the magnetic circuit for the carriage coil includes (magnet 58a)-(yoke 55)-(yoke 61)-(yoke 59)-(magnet 58a),
And (magnet 58b)-(yoke 60)-(yoke 59)-(magnet 58b).

According to the configuration of the second embodiment described above, 2
Since there is no guide rail between the objective lenses 10, the objective lenses can be brought closer to each other. Therefore, the present invention can be applied to a cartridge having a small opening. Further, the difference in the angle with respect to the tangential direction at the position where the light spot is formed becomes smaller between when the objective lens is located inside the disk 1 and when the objective lens is located outside, so that the track error signal Changes can be reduced.

The magnetic circuit for the focus coil is
Since the optical pickup is formed on the fixed portion, the weight of the optical pickup can be reduced. Further, since the yoke 55 also serves as a guide member for guiding the pickup in the X direction, and also as a magnetic circuit for the focus coil and the carriage coil, the number of parts can be reduced, and the size of the entire apparatus can be reduced. Can be achieved. Furthermore, since the bearing is configured to be located in the magnetic gap, the size can be further reduced, and the size can be reduced even in the height direction.

FIGS. 7 and 8 are a partially exploded perspective view and a side view, respectively, of the device according to the third embodiment of the present invention. FIG. 9 is a view showing the state of the lines of magnetic force acting on the focus coil according to the third embodiment. FIG.

In the third embodiment, an L-shaped focus coil 70 is mounted on the bottom surface of the lens holder 50. 8, an arm 72a is attached to the upper surface of the carriage 72, and a mirror 17 is fixed to the tip of the arm 72a and inserted into an opening 50b (see FIG. 7) provided in the lens holder 50. The light beam from the fixed optical system 41 is guided to the objective lens 10. The opposite end of the arm 72a is fixed to a fixing member 14 for fixing the support spring 13 that supports the lens holder 50 so as to be movable in the focus direction. Bearing holders 72b, 72b are provided on both sides of the carriage 72 in the X direction near the objective lens, and thread-wound reference bearings 73a are obliquely press-fitted and fixed to the disc 1 in the respective holders. . A spring 71 is fixed to the rear side of the fixing member 14, and a preload bearing 73 b is provided at a tip end of the spring 71.
It is press-fitted and fixed to face 3a.

The fixed portion is formed so that the long sides of the yoke 74 and the L-shaped yoke 75 extend in the X direction. A 90 ° notch is formed. The guide rails 30 and 31 are located in the cutouts. The guide rails 30 and 31 are fixed to a base (not shown).
The periphery of the inner yoke 74 is covered with a short ring 74a made of a copper pipe so as to reduce the inductance of the carriage coil 53 and improve responsiveness.
A magnet 76 is fixed to the inner side surface of the outer yoke 75, and a magnet 77 is disposed at the center of the inner yokes 74, 74. These magnets are arranged so that the same poles face each other, as in the above-described embodiment.

FIG. 9 is a diagram showing the directions of the lines of magnetic force acting on the focus coil 70. Since the directions of the lines of magnetic force acting on the portions 70a and 70b of the focus coil 70 parallel to the X direction are opposite to each other as shown in FIG. 9, the forces generated in the 70a and 70b are the same in the Z direction. Work in the direction. The magnet 77 formed at the center of the fixed portion is shared by the focus coil 70 and the carriage coil 53.

In the third embodiment, the efficiency of the focus coil is high because the utilization factor is high. Further, since the preload spring 71 is configured to be located in the magnetic gap, the size can be further reduced.

[0045]

According to the present invention, the size of each optical pickup in the track direction can be reduced, and even if a plurality of optical pickups are arranged in the track direction, they can be accommodated in the opening of a general cartridge. Therefore, recording / recording of information on / from an information recording medium stored in a generally used cartridge without preparing a special cartridge.
It can be applied to playback as it is.

Further, a guide member for guiding the carriage in a direction perpendicular to the track, a driving means for driving the objective lens in the focus direction, and / or a part of the driving means for driving the carriage in the direction perpendicular to the track are provided by a plurality of parts. Since the optical pickup is commonly used, the number of parts can be reduced, and the manufacturing cost can be reduced.

In the embodiment of the present invention, all the components including the carriage on which the objective lenses of the plurality of optical pickups are mounted are mounted in the same shape with the directions changed by 180 ° from each other. Savings can be achieved. Further, since the carriages have the same shape, the reference guide member can be shared, and the positional accuracy between the carriages can be increased.

Further, in the embodiment of the present invention, the support member for supporting the carriage is laid out obliquely when viewed from the X direction, and the support member and the driving means of the carriage are laid out vertically. Therefore, the size of the optical pickup in the track direction can be reduced.

Further, since the objective lenses are arranged so as to be shifted from the drive centers of the respective carriages in a direction approaching each other, the distance between the objective lenses can be further reduced.

[Brief description of the drawings]

FIG. 1 is a plan view showing a first embodiment of the present invention.

FIG. 2 is a partially exploded perspective view showing the first embodiment of the present invention.

FIG. 3 is a side view showing the first embodiment of the present invention.

FIG. 4 is a plan view showing a modification of the first embodiment of the present invention.

FIG. 5 is a partially exploded perspective view showing a second embodiment of the present invention.

FIG. 6 is a side view showing a second embodiment of the present invention.

FIG. 7 is a partially exploded perspective view showing a third embodiment of the present invention.

FIG. 8 is a side view showing a third embodiment of the present invention.

FIG. 9 is a diagram illustrating a state of magnetic lines of force acting on a focus coil according to a third embodiment of the present invention.

FIG. 10 is a plan view showing a conventional optical pickup device.

FIG. 11 is a plan view of a cartridge that stores an optical disk.

FIG. 12 is a perspective view for housing another conventional optical pickup device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Optical disk 2 Track 3 Spindle motor 4 Cartridge 5 Cartridge opening 10 Objective lens 11, 50 Lens holder 12, 51, 70 Focus coil 13 Support spring 14 Holding member 15, 32, 35, 56, 57, 58, 76, 77 Magnet 17 Mirror 18, 52, 72 Carriage 19c, 53a, 73a Bearing 19b, 53b, 73b Preload bearing 20, 71 Spring 22, 53, Carriage coil 30, 31 Guide rail 55a Guide groove 33, 34, 36, 37, 55, 59, 60, 61, 7
4, 75 yoke 41a. 41b Fixed optical system

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-59-5445 (JP, A) JP-A-3-62369 (JP, A) JP-A-63-146230 (JP, A) 260918 (JP, A) JP-A-4-113535 (JP, A) JP-A-4-113537 (JP, A) JP-A-61-3524 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G11B 7/085 G11B 7/09 G11B 7/095 G11B 7/14

Claims (4)

(57) [Claims] 1. An optical information recording medium comprising: two optical elements for irradiating a light spot on an information recording surface of the optical information recording medium; two carriages on which these optical elements are respectively mounted ; One side viewed in the diameter direction of the recording medium
And support means for movably supporting in a first direction crossing an information recording track formed on the information recording medium , and driving the plurality of optical elements in a second direction substantially perpendicular to the information recording surface. In an optical pickup device comprising an optical element driving means and a driving means for independently moving the two carriages in the first direction, a center of gravity of the optical pickup including the carriage and a member supported by the carriage And a drive center of the drive unit coincides with the drive unit, and at least a part of the support unit is commonly used to support the plurality of carriages. 2. An optical information recording medium comprising: a plurality of optical elements for irradiating a light spot on an information recording surface of the optical information recording medium; a plurality of carriages on which these optical elements are respectively mounted ; One side seen in the diameter direction of
A supporting means for movably supporting a first direction transverse to a direction of an information recording track formed on the information recording medium , and the plurality of optical elements being substantially perpendicular to the information recording surface. an optical element driving means for driving each independently in a second direction, each independently of the plurality of carriages in the first direction
An optical pickup device comprising: a carriage driving unit for moving the plurality of optical elements in the second direction; and at least a part of the optical element driving unit is commonly used for driving the plurality of optical elements in the second direction. And / or at least a part of the carriage driving means is commonly used for driving the carriage in the first direction. 3. A plurality of optical elements for irradiating a light spot on an information recording surface of the optical information recording medium, a plurality of carriages for mounting these optical elements, said these carriages optical information recording One side seen in the diameter direction of the medium
Supporting means for movably supporting an information recording track formed on an information recording medium in a first direction crossing the information recording track; and independently supporting the plurality of optical elements in a second direction substantially perpendicular to the information recording surface. an optical element driving means for driving the said plurality
Of the optical pickup apparatus comprising a carriage drive means for moving each independently a carriage in the first direction, the optical element driving means comprises a magnetic circuit for driving the optical element driving coils and optical element, the optical An optical pickup device, wherein at least a part of an element driving magnetic circuit is commonly used for driving the plurality of optical elements in the second direction. 4. A two optical elements for irradiating a light spot on an information recording surface of the optical information recording medium, and placed these optical elements respectively, the diameter direction of the optical information recording medium
, Two movable parts configured to be movable in a first direction crossing the direction of the information recording track formed on the information recording medium , and the two optical elements are arranged on the information recording surface. Optical element driving means for independently driving in substantially perpendicular second directions, supporting means for supporting the two movable parts so as to be movable in the first direction, and the first movable part for moving the two movable parts to the first direction. An optical pickup device comprising a movable portion driving means for independently moving in the directions, a center of gravity and a drive center of an optical pickup including the movable portion and a member supported by the movable portion coincide with each other, and the two optical elements are , Are arranged so as to be shifted from the respective centers of the two movable portions in a direction approaching each other when viewed in the first direction ,
At least a part of the supporting means and the driving means is
In driving the two movable parts in the first direction,
An optical pickup device characterized by being commonly used .